1. Field of the Invention
This invention relates to a character processing system capable of performing spelling checks.
2. Description of the Prior Art
In the spelling checks hitherto performed in this kind of character processing system, the conventional method consists in compiling a two-dimensional table with words in the European language dictionary arranged typically of the order of the initial letters in such words and of the numbers of characters of which such words are composed and then retrieving any appropriate words from the two-dimensional table. This retrieval method, as explained with reference to the words beginning with the letter "C" as shown in Table 5a and Table 5b, works with 1,006 entries of words having "C" in the initial position and composed of seven letters, similarly 1,154 word entries having "C" in the initial position and composed of eight letters, and as many as 1,092 word entries having "C" in the initial position and composed of nine letters, with the result that a retrieval of the word, "COMPANY," for example, is performed at least 1,006 times (503 times in the case of such a retrieval by the dichotomizing search method) during comparing and referring operations of the two-dimensional table. Furthermore, in regard to the retrieval of words from a dictionary of European language words which are classified merely by their order based on the initial letters, more frequent comparing and referring operations are performed.
However, in the spelling checks of the dictionary of the European language words for the character processing system described above, the processing speed for retrieval is very slow, so that the system is not adequately usable for any real-time processing of words with a typewriter or the like. Another available method is found in increasing the processing speed by turning words into hash codes, however, in consideration of the correcting function (for correcting misspelling), which is required immediately after the realization of the spelling check function, a dictionary employing hash codes presents a problem in that it has a low degree of accuracy because the dictionary is not capable of reproducing the original array of letters.
Furthermore, it has not yet been established in the current state of the art how the word data should be edited in a dictionary of words for European language writings, in spite of the fact that the volume of the capacity of the dictionary and the efficiency of retrieval are influenced by the specific method of editing the word data.
This is due to the fact that the word data are composed of a large number of items, and additionally, that peculiar relations exist among word data since such data contain many changes in form, including plural forms and conjugated forms for example. This reflects in a failure to readily attain a reduction of the capacity of the dictionary without decline in the efficiency of retrieval although the shift code method, the compact code method, and the Huffman code method have hitherto been known as methods of storing data with high efficiency in a data base (Information Processing Society of Japan; The 18th General Meeting (1977), Lecture Summary pp 65-66 and The 19th General Meeting (1978), Lecture Summary pp 855-856).